Names | |
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Preferred IUPAC name
(9R)-1-[(2R,3S,4R,5R)-5-(6-Amino-9H-purin-9-yl)-4-hydroxy-3-(phosphonooxy)oxolan-2-yl]-3,5,9-trihydroxy-3,5,10,14,19-pentaoxo-8,8-dimethyl-2,4,6-trioxa-18-thia-11,15-diaza-3λ5,5λ5-diphosphahenicosan-21-oic acid | |
Identifiers | |
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ChemSpider | |
ECHA InfoCard | 100.007.596 |
MeSH | Malonyl+CoA |
PubChem
CID
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UNII |
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CompTox Dashboard (
EPA)
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Properties | |
C24H38N7O19P3S | |
Molar mass | 853.582 |
Except where otherwise noted, data are given for materials in their
standard state (at 25 °C [77 °F], 100 kPa).
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Malonyl-CoA is a coenzyme A derivative of malonic acid.
It plays a key role in chain elongation in fatty acid biosynthesis and polyketide biosynthesis.
Malonyl-CoA provides 2-carbon units to fatty acids and commits them to fatty acid chain synthesis.
Malonyl-CoA is formed by carboxylating acetyl-CoA using the enzyme acetyl-CoA carboxylase. One molecule of acetyl-CoA joins with a molecule of bicarbonate, [1] requiring energy rendered from ATP.
Malonyl-CoA is utilised in fatty acid biosynthesis by the enzyme malonyl coenzyme A:acyl carrier protein transacylase (MCAT). MCAT serves to transfer malonate from malonyl-CoA to the terminal thiol of holo- acyl carrier protein (ACP).
Malonyl-CoA is formed in the first step of mitochondrial fatty acid synthesis (mtFASII) from malonic acid by malonyl-CoA synthetase ( ACSF3). [2] [3]
MCAT is also involved in bacterial polyketide biosynthesis. The enzyme MCAT together with an acyl carrier protein (ACP), and a polyketide synthase (PKS) and chain-length factor heterodimer, constitutes the minimal PKS of type II polyketides.
Malonyl-CoA is a highly regulated molecule in fatty acid synthesis; as such, it inhibits the rate-limiting step in beta-oxidation of fatty acids. Malonyl-CoA inhibits fatty acids from associating with carnitine by regulating the enzyme carnitine acyltransferase, thereby preventing them from entering the mitochondria, where fatty acid oxidation and degradation occur.
Malonyl-CoA plays a special role in the mitochondrial clearance of toxic malonic acid in the metabolic disorder combined malonic and methylmalonic aciduria (CMAMMA). [4] In CMAMMA due to ACSF3, malonyl-CoA synthetase is decreased, which can generate malonyl-CoA from malonic acid, which can then be converted to acetyl-CoA by malonyl-CoA decarboxylase. [2] [4] In contrast, in CMAMMA due to malonyl-CoA decarboxylase deficiency, malonyl-CoA decarboxylase is decreased, which converts malonyl-CoA to acetyl-CoA. [4]